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<script>
    function myinstanceof(instance, constructFunc){
       
        var t = typeof instance;
        if(t!== "object" || t === null) return false
        var instance_proto = instance.__proto__
        var proto_address = constructFunc.prototype
        while(1){
            if(instance_proto === null){
                return false
            }else if(proto_address === instance_proto){
                return true
            }
            instance_proto = instance_proto.__proto__
        }
    }
    var obj = {
        a: 11
    }
    console.log(myinstanceof(obj, Object))
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